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151.
152.
153.
This paper attempts to investigate the problem for the interaction between a uniformly moving screw dislocation and interface rigid lines in two dissimilar.anisotropic. materials. Integrating Riemann-Schwarz's symmetry principle with the analysis singularity of complex functions, we present the general elastic solutions of this problem and the closed form solutions for interfaces containing one and two rigid lines. The expressions of stress intensity factors, at the rigid line tips and image force acting on moving dislocation are derived explicitly. The results show that dislocation velocity has an antishielding effect on the rigid line tip and a larger dislocation velocity leads to the equilibrium position of dislocation closing with the rigid line. The presented solutions contain previously known results as the special cases. 相似文献
154.
In this article we make a full study of the class of non-degenerate real planar quadratic differential systems having all
points at infinity (in the Poincaré compactification) as singularities. We prove that all such systems have invariant affine
lines of total multiplicity 3, give all their configurations of invariant lines and show that all these systems are integrable
via the method of Darboux having cubic polynomials as inverse integrating factors. After constructing the topologically distinct
phase portraits in this class we give invariant necessary and sufficient conditions in terms of the 12 coefficients of the
systems for the realization of each one of them and give representatives of the orbits under the action of the affine group
and time rescaling. We construct the moduli space of this class for this action and give the corresponding bifurcation diagram.
Dedicated to Professor Zhifen Zhang on the occasion of her 80th birthday 相似文献
155.
156.
用Nd :YAG激光烧蚀Al靶获得等离子体 ,激光脉冲能量为 145mJ·pulse-1,光源中通入Ar气作保护气体 ,压强为 10 0Pa。利用时间分辨技术获得纳秒级时间分辨光谱。分析了等离子体连续辐射、连续辐射的吸收、Al原子谱线辐射的时间演化规律 ,并进行了简短的讨论。结果发现 ,低真空时激光诱导Al等离子体的连续辐射、连续辐射的吸收、Al原子谱线辐射的时间演化规律以及它们之间的相互关系 ,与常压时的情况十分相似 相似文献
157.
M. Czanta C. Strietzel H. J. Besch H. F. Beyer F. Bosch R. Deslattes F. Förster A. Gumberidze G. Hölzer P. Indelicato C. Kozhuharov O. Klepper A. Krämer D. Liesen T. Ludziejewski X. Ma B. Manil G. Menzel N. Pavel A. Simionovici M. Steck T. Stöhlker S. Toleikis J. Tschischgale A. H. Walenta O. Wehrhan 《Hyperfine Interactions》2001,132(1-4):487-490
Crystal spectrometry and absorption edge technique have the capability to overcome the gap in accuracy between experiment
and theory in the strong field domain of QED. New results are presented which indicate the capacity of these methods to measure
the energies of X-rays emitted by highly charged heavy ions at modern storage rings with a precision sensitive to second order
corrections to the Lambshift in H-like very heavy ions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
158.
《Current Applied Physics》2015,15(11):1296-1302
One-dimensional ZnO materials have been promising for field-emission (FE) application, but how to facially control the alignment of ZnO emitters is still a great challenge especially for patterned display application. Here, we report the fabrication of novel ZnO nanowire (NW) line and bundle arrays for patterned field-electron emitters. The effects of PS template size and heating time on the resulted ZnO nanoarrays were systematically studied. The deformation degree of PS templates was controlled and hence utilized to adjust the alignment of electrochemically deposited ZnO arrays. It was found that the length of NW lines and the density of NW bundles can effectively tuned by the PS template heating time. The optimal FE performance with turn-on electric field as low as of 4.4 V μm−1 and the field-enhancement factor as high as of 1450 were achieved through decreasing the screening effect among the patterned field-electron emitters. 相似文献
159.
160.
We generalize the surface growth model of Gates and Westcott to arbitrary inclination. The exact steady growth velocity is
of saddle type with principal curvatures of opposite sign. According to Wolf, this implies logarithmic height correlations,
which we prove by mapping the steady state of the surface to world lines of free fermions with chiral boundary conditions. 相似文献